1. Field of the Invention
The present invention relates in general to a percutaneous catheterization system, and, in particular, to a catheter anchoring system which securely interconnects an indwelling catheter with a tubing and securely anchors such interconnection to a patient""s skin.
2. Description of Related Art
Medical treatment of patients commonly involves the use of percutaneously inserted catheters to direct fluids directly into the bloodstream, a specific organ or an internal location of the patient, or to monitor vital functions of the patient. For instance, intra-arteriosus catheters are commonly used to direct fluids and/or medication directly into the bloodstream of the patient. Epidural catheters are commonly used to direct anesthesia into an epidural space to anesthetize a specific location of the patient. Intervascular catheters are commonly used to monitor arterial blood pressure.
The fluid (e.g., parenteral liquid, medication or anesthesia) typically drains from a container positioned above the patient. The fluid flows through tubing and into an indwelling catheter. The catheter and fluid tubing are commonly removably attached by a conventional lure-type connector, such as the type described in U.S. Pat. No. 4,224,937.
In common practice, a health care provider, such as, for example, a nurse or doctor (for ease of description, as used herein the term xe2x80x9cnursexe2x80x9d will refer to health care providers generally and will not be restrictive in meaning), uses adhesive or surgical tape to maintain the catheter in place on the skin of the patient. The connection between the tubing and the catheter is likewise maintained by use of tape.
The nurse may also form a safety loop in the tubing so that any tension applied to the tubing does not directly pass to the catheter cannula, but rather is absorbed by the slack of the safety loop. The nurse typically loosely tapes the loop to the skin of the patient.
This entire taping procedure takes several minutes of the valuable time of the health care provider. Furthermore, nurses commonly remove their gloves when taping because most nurse find such taping procedures difficult and cumbersome when wearing gloves.
The catheterization process often requires frequent disconnection between the catheter and the fluid supply tube. For instance, intravenous catheterization is frequently maintained for several days, depending upon the condition of the patient. The catheter tubing is generally replaced every 24 to 48 hours in order to maintain the sterility of the fluid and the free-flow of the fluid through the tubing. A nurse must thus frequently change the tubing and retape the connection. Moreover, the tape, which secures the catheter to the skin of the patient, often covers the cannula insertion point. The nurse must remove the tape to inspect the insertion point for inflammation or infection, and must then repeat the above-described taping procedure.
A great deal of valuable time is thus used in applying significant amounts of surgical tape to indwelling catheters. The frequent application and removal of surgical tape also commonly results in the excoriation of the skin of the patient in the area of the insertion.
A number of catheterization systems have recently been developed which improve the stabilization of the catheter system and obviate the need for frequent application and removal of surgical tape. One such system is disclosed by U.S. Pat. No. 5,192,273 issued to the present Applicant, which is hereby incorporated by reference.
The ""273 patent discloses an adaptor which interconnects the catheter with a fluid supply tubing. The adaptor snaps into a base attached to the patient""s skin by an adhesive pad. Specifically, a nurse presses the adaptor between upstanding legs of the base. Detents on the adaptor legs slide into corresponding annular grooves in the adaptor body to hold the adaptor to the base.
Although the base holds the adaptor securely in place, a nurse may have difficulty positioning and aligning the annular grooves of the adaptor with the detents on the base. Exigent circumstances may further exacerbate the difficulties associated with properly positioning the adaptor onto the base. Some nurses and other health care providers may also have trouble determining how to engage the catheter adaptor with the base.
The catheter anchoring system of the present invention provides an adaptor retainer which is not position or technique sensitive. That is, the nurse simply locates the catheter adaptor generally above the retainer, and presses the adaptor into the retainer. Engagement requires only coarse alignment of the adaptor with the retainer.
In accordance with one aspect of the present invention, an anchoring system is provided for use with a catheter having at least one groove or recess which extends around the circumference of the catheter or the catheter adaptor. The anchoring system comprises a retainer that includes first and second channel portions. The channel portions extend about a longitudinal axis, and each is configured to receive a corresponding portion of the catheter adaptor. A plurality of projections are positioned upon the walls of the retainer and extend inwardly into the channel. At least one of the projections is positioned between the first and second channel portions. Each projection is dimensioned to as to fit within the recess upon the catheter adaptor to prevent the catheter from moving in a longitudinal direction. If multiple grooves are used, they may be arranged at different positions along the longitudinal axis of the catheter adaptor so as to provide multiple positions in which the projection of the retainer may be inserted into one of the grooves of the adaptor.
Another aspect of the present invention involves a catheterization system includes a catheter and a retainer to secure the catheter to a patient. The catheter includes a fitting with a groove which extends about the circumference of the fitting. The retainer includes first and second channel portions that extend about a longitudinal axis. Each channel portion generally has a truncated cross-sectional shape with an opening along the longitudinal axis. Each channel is also sized to surround at least a portion of the fitting through an arc of greater than 180 degrees about the longitudinal axis. At least one projection of the retainer extends generally into the channel toward the longitudinal axis and lies between the first and second channel portions. The projection has a longitudinal length so dimensioned to substantially equal the width of the groove of the catheter fitting and to be generally less than the combined longitudinal lengths of the first and second channel portions. This dimensional relationship between the channel portions and the projection provides lateral stability of the catheter fitting when the projection is inserted within the groove of the fitting.
The retainer further comprises a central channel which extends through the retainer about an axis which is generally parallel to the longitudinal axis. The channel is interposed between the opposing longitudinal walls and has a truncated circular cross-sectional shape. The central channel, in cross-section, is sized to encompass the tubular body of the catheter through an angle greater than about 180xc2x0.
The anchoring system may additionally comprise a tube clip configured to receive a portion of the catheter tube. The anchoring system may also comprise an S-clip having a plurality of retainers to secure a microbore tubing connected to the tube by the adaptor.
An additional aspect of the present invention provides a catheter anchoring system for securing an indwelling catheter within a body lumen of a patient and for securely interconnecting the indwelling catheter with a tube. The catheter anchoring system comprises a catheter adaptor having a generally tubular body defined between distal and proximal ends. The distal end is configured to engage the catheter proximal end and the proximal end is configured to couple to a distal end of the supply tube. The catheter adaptor additionally comprises a groove which extends about the circumference of the tubular body of the adaptor.
A retainer of the catheter anchoring system comprises a longitudinal channel configured to receive the tubular body of the adaptor in a snap fit manner. The retainer additionally comprises a plurality of projections which are sized to fit within a groove upon the adaptor when the adaptor is positioned within the channel. The retainer prevents the adaptor from sliding in a longitudinal direction when one of the grooves of the adaptor receives the projection of the retainer.
In a preferred embodiment, there may be a plurality of grooves disposed upon the adaptor. In an alternative preferred embodiment, the projection of the retainer may comprise a truncated annular collar which extends inwardly into the channel of the retainer, and which fits within the groove which circumscribes the tubular body of the catheter or catheter adaptor.
In accordance with a preferred method of anchoring an indwelling catheter/tube interconnection to a patient, an adaptor is provided having a generally tubular body with one or more recesses. An anchor pad is also provided with an adhesive back. The anchor pad supports a retainer configured to receive the adaptor and has a channel with one or more projections. The anchor pad is attached to the patient""s skin proximate to an indwelling catheter. The recesses of the adaptor are positioned above the projection of the retainer. The retainer is deflected so as to open the channel to a size sufficient to receive the adaptor, and the adaptor is inserted into the channel. The projection is inserted into one of the recesses. The retainer is then permitted to spring back to an undeflected position such that the tubular body is captured within the retainer.